Conventional approaches for cardiac valve replacement require the cutting of a relatively large opening in the patient's sternum (“sternotomy”) or thoracic cavity (“thoracotomy”) in order to allow the surgeon to access the patient's heart. Additionally, these approaches require arrest of the patient's heart and a cardiopulmonary bypass (i.e., use of a heart-lung bypass machine to oxygenate and circulate the patient's blood). In recent years, efforts have been made to establish a less invasive transcatheter cardiac valve replacement procedure, via either a transvascular approach, i.e. delivering the new valve through the femoral artery, or by transapical route, where the replacement valve is delivered between ribs and directly through the wall of the heart to the implantation site.
Valve stents for use within a human body usually comprise a valve component and a stent component. The stent component is configured to house at least a portion of the valve component. According to some known proposals (see e.g. WO 2009/053497), the stent component further includes a lower anchoring crown comprising an at least partly conical body, the lower anchoring crown defining the proximal end of the stent component. The stent component further comprises an upper anchoring crown in communication with the lower anchoring crown and comprising an at least partly conical body, whereby the conical body of the lower anchoring crown slopes outwardly in the direction of the proximal end, and the conical body of the upper anchoring crown slopes outwardly in the direction of the distal end. A conical or cylindrical commissural post section is located distally of the distal end of the upper anchoring crown. Further distally, a stabilization arch section is comprised. WO 2012/032147 describes an example of delivery catheter for introducing an expandable stent-valve to the patient's heart.
While less invasive and arguably less complicated, percutaneous heart valve replacement therapies (PHVT) still face various challenges, including ease of use of a delivery system for the replacement valve, which can directly influence the inability for a surgeon to ensure proper positioning and stability of the replacement valve within the patient's body.